The macroscopic dielectric function of crystalline silicon is calculated within density-functional theory, considering exchange and correlation effects beyond the local-density approximation. Reproposing an original idea of Hohenberg and Kohn, we consider a functional based on the exchange and correlation kernel of the homogeneous electron gas, K-xc(HEG). The same kernel is used in:the evaluation of the dielectric matrix, keeping local-held effects into account. The results, compared with those obtained in the local-density approximation, show a limited reduction of the well-known overestimation of the macroscopic dielectric constant. Results obtained for optical and energy loss spectra are also presented. [S0163-1829(99)00344-6].
Olevano, V., Palummo, M., Onida, G., Del Sole, R. (1999). Exchange and correlation effects beyond the LDA on the dielectric function of silicon. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 60(20), 14224-14233.
Exchange and correlation effects beyond the LDA on the dielectric function of silicon
PALUMMO, MAURIZIA;
1999-01-01
Abstract
The macroscopic dielectric function of crystalline silicon is calculated within density-functional theory, considering exchange and correlation effects beyond the local-density approximation. Reproposing an original idea of Hohenberg and Kohn, we consider a functional based on the exchange and correlation kernel of the homogeneous electron gas, K-xc(HEG). The same kernel is used in:the evaluation of the dielectric matrix, keeping local-held effects into account. The results, compared with those obtained in the local-density approximation, show a limited reduction of the well-known overestimation of the macroscopic dielectric constant. Results obtained for optical and energy loss spectra are also presented. [S0163-1829(99)00344-6].Questo articolo è pubblicato sotto una Licenza Licenza Creative Commons